Volume 72, Issue 3

A highly alkaline pectin lyase (PNL) produced by Fusarium lateritum MTCC 8794 using solid-state fermentation was purified and biochemically characterized. The enzyme was purified to homogeneity by comparatively simple method involving ammonium sulfate precipitation and cation exchange chromatography resulting in a final purification fold of 5.5 with specific activity of 1.9 U/mg and yield of 3.42%. The SDS-PAGE of the purified enzyme revealed a single protein band of approximately 16 kDa. The pH optimum was found to be 10.0, while the enzyme was stable in the pH range 6.0–10.0. The optimum temperature of the purified PNL was 40 ◦ C, the enzyme being stable upto 50 ◦ C for 30 min. The K m value calculated by Michaelis-Menten curve was found to be 0.79 mg/mL, while V max and k cat of the purified enzyme were found to be 0.57 international unit and 41.6 s −1 , respectively. The enzyme showed inhibition by most of the divalent cations at 1 mM concentration.

The EST3 gene of Saccharomyces cerevisiae encodes one of the essential subunits of telomerase enzyme. Expression of the EST3 gene is regulated at the translation level by +1 programmed ribosomal frameshift (PRF). It is known that physiological stress affects telomere length. In this study, we have investigated the effects of different types of stresses and stress activated protein kinases on the frameshift rate in EST3 gene. PRF rate of EST3 gene was measured as 13% in the normal growth conditions in the wild type cells. But, the PRF rate of EST3 in the wild type strain grown in glucose limited conditions decreased more than 6-fold. Contrary to glucose limitation, osmotic stress increased frameshift rate from 13% to 25%. Amino acid starvation and boron stress also activate PRF rate by 2-fold in EST3 in a Gcn2 dependent manner. When the PRF rate was analysed in gcn2 and snf1 mutants, frame shift rate of EST3 was approximately 6% in normal growth conditions. It seems that the basal level expression of EST3 is highly dependent on the Gcn2 kinase complex, indicating that Gcn2 might have a significant function in connecting the stress signals to biosynthesis of the full-length Est3 peptide. This regulation might connect the biosynthesis of functional telomerase and telomere replications to cell physiology through stress activated protein kinases.

Urinary tract infections (UTIs) are one of the most frequent infections in elderly people. The majority of infections is caused by uropathogenic E. coli. These strains contain a broad spectrum of virulence factors and are able to overcome defense barriers and colonize host organism. Population of elderly individuals has been growing globally and for that reason it is possible to expect a rise of UTIs among them. The aim of this study was to determine the phylogenetic group (A, B1, B2 and D) of urinary strains of E. coli isolated from elderly patients and evaluate the presence of 14 virulence genes ( hly , cnf1 , cdt , sat , afa , sfa , pap , aer , upaH , cah , pic , neuC , kpsMT II and traT ) in these strains. We have carried out a phylogenetic analysis and virulence genes identification of 75 urinary E. coli isolates. Among our 75 E. coli strains, phylogenetic group B2 (64%) was the most dominant followed by groups D (16%), B1 (10.7%) and A (9.3%). The genes kpsMT II (65.3%), traT (61.3%), upaH (58.6%) and aer (52.0%) were found to be the most prevalent. We identified from 5 to 10 virulence genes in 44% strains belonging to B2 phylogroup. E. coli urinary strains examined in this study belonged mainly to phylogenetic group B2. We have also found that the majority of examined virulence genes, which are crucial for the establishment and maintenance of infection, were present in these strains.

Desert annual plant species are valuable pasture forage and sources for restoration of degraded pastures. Examining the impact of environmental stresses on genetic diversity and population structure can identify species populations suitable for habitat restoration. We examined allozyme diversity and population structure of two annual species, halo-xerophyte Salsola incanescens and xero-halophyte S. paulsenii , in association with the type of desert plant community, which reflects the water-salt conditions in the soil. We sampled 19 wild populations in 15 xerophytic, xero-halophytic and halophytic plant communities in Kyzylkum desert (Uzbekistan, Central Asia). The species studied had low genetic variability ( P 95 = 0.05–0.10, H O = 0.008–0.025) and high population structure ( F ST = 0.585–0.739). Wright’s fixation index indicated deviations from Hardy–Weinberg equilibrium with a deficit of heterozygotes ( F IS = 0.79) in S. incanescens populations. No evidence of isolation by distance was found for the species studied (Mantel’s r = 0.02–0.04). Estimates of genetic variability in populations from xerophytic and halophytic plant communities differed significantly (2- to 10-fold, P< 0.05) for both species. Moreover, allele–habitat associations at the GOT and Me loci were found in both species. Decreased levels of within-population variability were found in both species in halophytic communities. In sub-optimal habitats, the decline in genetic differentiation and increase in gene flow were found for both S. incanescens (xerophytic plant communities) and S. paulsenii (halophytic communities). Our results indicate that genetic diversity rather than population differentiation is affected by the habitat type.

The anatomical structure of the leaf and stem of nine Micromeria species from the Balkan Peninsula was investigated with the aim to establish the adaptive characteristics and traits that could be useful in the identification of species and subgeneric classification. The species included in the anatomical analysis were: Micromeria albanica (Griseb. ex K. Malý) Šilić , M.thymifolia (Scop.) Fritch , M. pulegium (Rochel) Bentham, M. dalmatica Bentham of section Pseudomelissa and M. cristata (Hampe) Griseb., M. kosaninii Šilić, M. juliana (L.) Bentham ex Reichenb., M. croatica (Pers.) Schott M. parviflora (Vis.) Reichenb. of section Micromeria . Variability of 17 quantitative characters of the leaf (thickness, height of adaxial and abaxial epidermis, thickness of the palisade and spongy tissue) and stem (radius, cortex thickness, thickness of the vascular cylinder, phloem, xylem, pith radius) was examined. Multivariate analysis of variance (ANOVA), principal component analysis (PCA), canonical discriminant analysis (CDA) and UPGMA clustering method based on Mahalanobis’ distances were used to determine the variability structure and level of importance of the anatomical differentiation of the investigated taxa. Qualitative characters were also included in the consideration of the anatomical variability, such as leaf shape, leaf margin, position of sclerenchyma fibers in the leaf and stem. The results showed that investigated Micromeria species posses a xeromorphic general structure plan, but each species has achieved distinctive adaptations according to its specific genetic potential. The results have shown a clear difference between the species belonging to the different sections of genus Micromeria , so they have a potential diagnostic and systematic value.

Proline, 24-epibrassinolide and diphenylene iodonium are few of the novel antioxidant molecules, involved in growth regulation and abiotic stress tolerance of plants. However, these are scarcely explored in relation to their role in arsenic stress tolerance. Therefore, present study was designed to investigate the involvement of proline, 24-epibrassinolide and diphenylene iodonium in conferring tolerance to Glycine max L. against arsenic toxicity. The results showed that arsenic caused decrease in growth attributes like germination percentage, radicle length and dry mass, which were accompanied by the accumulation of arsenic. The application of arsenic steeply reduced total lipid content while increased the levels of oxidative stress markers such as superoxide anion, hydroxyl radical, hydrogen peroxide, free fatty acid, conjugated diene, lipid hydroperoxide, malondialdehyde and 4-hydroxy-2-nonenal, and the activities of lipase and lipoxygenase. Impressively, proline, 24-epibrassinolide and diphenylene iodonium played their roles as protective agents, and caused enhanced growth and reduced arsenic accumulation. These protective molecules enhanced the total lipid content while reduced the levels of oxidative stress markers and activities of lipase and lipoxygenase. The results indicated that proline, 24-epibrassinolide and diphenylene iodonium served as potential inhibitors of As-induced oxidative stress in Glycine max L.

The present investigation was made to study the influence of hormones on leaf regeneration and mineral acquisition (Ca, K, Mg, Bo, Cd, Cr, Ni, Fe and Se) in Jatropha curcas using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The method employed direct induction of shoot buds from the leaves of four different genotypes (CSM-1, CSM-2, CSM-3, CSM-4) using Murashige & Skoog (MS) medium supplemented with thidiazuron (TDZ). Among all the four genotypes, CSM-2 developed the highest and early shoot bud regeneration. The best responding genotype was also treated with N-(2-chloro-4-pyridyl)-N-phenylurea (CPPU) and 6-benzyl aminopurine (BAP) to further enhance leaf regeneration. Highest regeneration was achieved using CPPU among all the cytokinins used, with more than 25 shoot buds per leaf explant. Mineral acquisition in CPPU treated explants was higher as compared to thidiazuron (TDZ) and BAP treated explants. Best shoot proliferation and elongation was obtained on MS medium supplemented with BAP, indole-3-acetic acid (IAA) and gibberellin (GA 3 ). This study not only provides an efficient protocol for propagation of J. curcas but also discuss about the differential response of genotypes influenced by cytokinin.

An in situ experiment to investigate periphytic community development was conducted on an artificial substrate (glass slides) in a Danube floodplain lake in Croatia. The main aim of the research was to analyze the structure of the ciliate community (Ciliophora, Protozoa) in the periphyton. We wanted to investigate how biotic and abiotic factors change and influence the ciliate community, reflecting not only the temporal community dynamics, but also the complex interactions within the periphyton. The experiment lasted from April to December 2009. To monitor the colonization process, the samples were collected on the 1 st , 3 rd , 5 th , 7 th and 14 th day of exposure. After that, sampling was conducted biweekly, with the aim of studying the successional patterns of the periphytic ciliate community. 116 ciliate taxa were recorded. Non-metric multidimensional scaling indicated that development of the periphytic ciliate community occurred in three phases: initial, intermediate and mature. Water temperature and transparency were the most important parameters influencing the initial and intermediate phases of community development when mainly vagile bacterivorous and algivorous ciliates were present. The mature phase was characterized by higher organic content in the periphyton and an increased concentration of chlorophyll in the water column, indicating the potential food source as the primary factor influencing ciliates. The complex three-dimensional structure of the periphyton also affected the ciliate assemblage throughout the later successional stages. The trophic structure of the ciliates became more diverse during the mature phase, with sessile suspension-feeding and predatory ciliates as dominant groups. The present study shows that the early stages of the periphytic ciliate community are influenced mainly by external abiotic factors, whilst the mature community is characterized by biotic factors.

In the crustacean Branchipus schaefferi cercopods are brightly coloured caudal rami at the end of the abdomen. The specific life environment of B. schaefferi (highly turbid puddles) may suggest that besides their mechanical function, cercopods may also play an ornamental role to attract a potential mate. We performed standardized major axis regression analyses of cercopod length against body length to determine the allometry. Each allometric slope of cercopod was compared with the median of slopes of non-sexual body parts: eye diameter, epipodit, and antennulae lengths. We also examined the relative differences in cercopods colouration between males and females within a population. Cercopods scaled slightly more positively when compared to both median slope of non-sexual traits as well as to typically used slope value 1. The difference in cercopods colouration between the sexes showed a strong sexual dimorphism. Sexual dimorphism in colouration and slightly positive allometry of cercopods support the hypothesis that this organ might be under the sexual selection and function as an ornament advertising fitness of an individual or a signal of sexual maturity of a male in highly turbid water.

This study evaluated the temporal and bathymetric distribution of the speckled swimming crab Arenaeus cribrarius from coastal waters of southern Brazil. Monthly samples were taken at five distinct depths throughout one year in the adjacent area from Babitonga Bay, Southern Brazil. Data on environmental conditions (temperature, salinity, granulometry and organic matter) were collected and their association was tested using Multiple Linear Regression and Principal Component Analysis. Juveniles and adults showed different distribution patterns according to depth, with juveniles being more abundant in the shallower areas. The increase in temperature favors the juvenile distribution, while the distribution of adults was related to finer sediments. The pattern of distribution observed for adults might be associated with burrowing habits, or with the search for colder (and consequently deeper) waters, which are richer in nutrients. The high abundance of juveniles in shallower areas might be influenced by the Coastal Water mass that provides higher water temperatures in the summer, and by the Babitonga Bay estuarine complex, which can be an important source of organic matter. We conclude that this region represents a nursery ground for the studied species and is essential to preserve Babitonga Bay in order to maintain A. cribrarius in this region, since this area has suffered from anthropic impacts.

The mating disruption technique using Checkmate ® VMB-XL pheromone dispensers, in combination with imidacloprid-based insecticide treatments through drip irrigation, was tested against vine mealybug in Tunisian vineyards for the first time in the South Mediterranean area. The number of male vine mealybugs caught in traps of mating disruption (MD) plots was significantly lower than that of Non-MD plots, indicating that the application of Checkmate ® VMB-XL significantly disrupted the male-female vine mealybug sexual communication. The cumulative effect of mating disruption on vine mealybug over time reached 120 days. Two months after Checkmate ® VMB-XL application, the density of mealybug nymphs and adult females on grapevine basal leaves was significantly reduced in all MD plots. The obtained results provide evidence that the application of Checkmate ® VMB-XL under Center-South Tunisian vineyard conditions proved to be very effective in confusing vine mealybug males and disrupting the mating process. The eventual future use of this technique in Integrated Pest Management programs in Tunisia is discussed herein.

Aphid species Brachycaudus divaricatae Shaposhnikov, 1956, originally described from Turkmenistan and earlier known from the Middle East and Eastern Europe only, is a successful invader to Central Europe. Its principal winter host, Prunus cerasifera , was originally distributed in Central Asia, Near East, and South Eastern Europe. Now it is common in Eastern and Central Europe. Brachycaudus divaricatae is closely related to native European aphid species Brachycaudus lychnidis (L., 1758). The aims of this study were: 1) to summarize and present the information on the distribution and host specificity of B.divaricatae from its invasive area in Europe; 2) to analyse and compare partial sequences of mitochondrial COI with those of nuclear EF-1 α from samples identified as B.divaricatae and B.lychnidis to find possible hybridization or incomplete lineage sorting between these species. Since the first record from Eastern Baltic region in 2002, B . divaricatae changed its distribution area significantly. Now this aphid species has already reached the northern edge of its winter host distribution area. Five COI and 10 EF-1 α haplotypes were detected among the analysed samples of B.divaricatae and B.lychnidis . The most abundant COI haplotype was common for both species. However, EF-1 α sequences were species-specific despite their minor differences. Coalescent simulations were performed using the model assuming no gene flow after the split between species and mimicking the parameters of empirical data. The analysis of genetic distances calculated for simulated data set supported the hypothesis of possible incomplete lineage sorting.

Numerous studies have investigated the nest-site characteristics and selection of bird species, because these features often play a determining role in bird breeding success. In recent years researchers focused on urban environments as a source of novel conditions which provide breeding opportunities for species that are able to survive in human-altered environments. Although thrushes Turdus spp. are among the species which frequently inhabit urban areas, the fieldfare Turdus pilaris only recently has started to colonize human settlements and reports on populations in urban ecosystem are rare. The aim of our study was to investigate the fieldfare density and nest-site selection in urban parks of Rzeszow, Poland. We found that the average density of breeding pairs in study area was 2.92 pair/ha. Fieldfares nested entirely on deciduous trees, despite the presence of numerous coniferous trees in parks. They built their nests mostly on those tree species which were the most abundant in particular study plot, which indicates that the studied urban population of the fieldfare is rather opportunistic in the selection of a nest-tree species. Also nest-tree surroundings consisted of the trees that dominated in the parks. The results of our study suggest that the fieldfare is among the species that synurbize easily and may reach even higher breeding densities in towns than in natural habitats.

Antioxidants can reduce the occurrence of long-term damages, caused by free radicals. In this study, we aimed to evaluate the effects of CuO nanoparticles and hydroalcoholic extracts of Berberis vulgaris , Descurainia sophia and Silybum marianum on catalase, glutathione peroxidase, and malondialdehyde concentrations in male diabetic rats. In case 50 Wistar rats (250–350 g) were divided in ten groups (five rats per group): healthy controls, healthy rats receiving nanoparticles, healthy rats receiving B. vulgaris, D. sophia, and S. marianum extracts (independently), diabetic controls, diabetic rats receiving CuO nanoparticles, and diabetic rats receiving the extracts independently. In diabetic groups, diabetes was induced in half of the rats, using alloxan at a dose of 120 mg kg −1 . In addition to CuO nanoparticles, the control and diabetic groups independently received 0.5 ml of B. vulgaris, D. sophia, and S. marianum extracts via intraperitoneal injection for 30 days. Then, the animals were anesthetized with ketamine and the liver tissues were removed. The concentrations of catalase, glutathione peroxidase, and malondialdehyde were measured and compared. In diabetic groups treated with CuO nanoparticles, a significant increase was reported in the concentration of malondialdehyde (from 4.7 ± 0.44 to 5.05 ± 0.40) (mean ± SD). Moreover, a significant decline was observed in the activity of catalase (from 36.8 ± 1.48 to 36.2 ± 1.48) and glutathione peroxidase enzymes (from 75.4 ± 3.91 to 72.4 ± 4.33). The results show that S. marianum extract was more effective than B. vulgaris and D. sophia extracts in diminishing the effects of CuO nanoparticles.